Compress MP3 Files
Make MP3s smaller three ways — by bitrate preset, by percentage of original size, or by exact file-size target.
Drop your audio file here
or click to browse a file
Pick a quality preset, target percentage of original size, or an exact file size in MB.
Mode
Quality preset
About the MP3 compressor
Three ways to compress, depending on what you actually need. The quality preset mode lets you pick a bitrate (Low / Medium / Standard / High / Max) and re-encode at that rate — best when you know roughly how much quality you're willing to trade. The percentage mode lets you target a fraction of the original size — handy when the source files vary in length but you want them all about half the size. The target file-size mode hits an exact MB number — the right choice when you have a hard cap (a 5 MB email attachment, a 25 MB Discord upload, a 10 MB podcast-host limit per episode).
Voice content compresses much further than music without losing intelligibility, so you can be more aggressive with podcasts and audiobooks than with songs.
How to compress an MP3 online
- 01
Drop the MP3
Pick the file you want to shrink. Other audio formats are accepted too.
- 02
Pick a mode
Quality preset for fixed bitrate, percentage for proportional shrink, or target MB for an exact cap.
- 03
Compress & download
Click compress — the smaller MP3 is ready in seconds.
Why compress MP3s here
- Three compression modes — bitrate preset, percentage of original, exact MB target
- Five quality presets covering voice and music (64k–256k)
- Hit an exact email or upload limit (1–25 MB)
- Free and private — we don't analyse or index your audio
- No file size login wall
- Works on any device, no install
Compression FAQ
Which mode should I use?
Quality preset if you know the bitrate you want. Percentage if you're batch-shrinking a folder and want everything roughly half the size. Target file size if you have a hard cap (Gmail's 25 MB, Discord's 10 MB, etc.).
How much smaller will my MP3 get?
Roughly proportional to the bitrate ratio. Going from 320k to 96k cuts the file to about 30% of its original size. The percentage and target-size modes are even more direct — they hit the size you ask for.
Will the audio sound worse?
Lowering the bitrate is lossy, so yes — but for spoken-word content 96k is essentially indistinguishable from the original. For music, stick to 128k+ to keep it crisp.
Can I compress non-MP3 files?
Yes. The tool accepts any input audio (WAV, FLAC, OGG, M4A, OPUS) and produces a smaller MP3.
Is my file kept private?
Yes. We don't analyse or index your audio, and processed files are deleted within 24 hours.
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